1. Field of the Invention
The present invention relates to contact pins for connecting IC-side leads to an external circuit board and an IC socket having a plurality of contact pins in order to perform an electrical test of IC, and more specifically to contact pins in which accuracy in an IC support position is improved and an IC socket.
2. Description of the Related Art
As shown in FIG. 14, an IC socket 100 of an open top type has a plurality of contact pins 101, which connects IC (e.g., QFP, SOP, TSOP) leads (not shown) to an external electrical test circuit (not shown) attached to a socket main body 102. In the socket main body 102, a cover 104, which has an IC insertion window 103, is supported to be movable up and down.
Then, when the cover 104 is depressed, the contact pins 101 shown in FIG. 14 are bent and deformed, so that the movable side pin 105 is depressed by the cover 104, a movable side contact portion 106 retracts from a fixed side pin 107 and an IC lead is guided onto the fixed side pin 107. Also, when the cover 101 returns to the original position, contact pins 101 press a lead 111 of an IC 110 to a fixed side contact portion 108 of the fixed side pin 107 by a restoring force, so that the lead 111 of IC 110 is sandwiched between the movable side contact section 106 and the fixed side contact portion 108 (see FIG. 15). Under this state, current-carrying to the lead 111 of IC 110 is established, and an electrical test of IC 110 is carried out.
When the electrical test of IC 110 ends, the cover 104 is depressed and the movable side contact portion 106 is retracted from the fixed side contact portion 108, and IC 110 is taken out of the IC socket 100.
In such IC socket 100, the tip of the lead 111 is brought into contact with the tip of a rib 112 of the socket main body 102, which divides the contact pins 101 so as to position IC 110 as shown in FIG. 16 in order that the above-mentioned electrical test is performed without fail. Thereafter, the lead 111 is sandwiched between the fixed side contact portion 108 and the movable side contact portion 106.
However, in the above-explained conventional IC socket, the pitch between leads is narrow. If the width of lead 111 has to be the same as that of the contact pin 101 or smaller than that of the contact pin 101, there occurs a case in which the tip of the lead 111 comes in a contact pint containing groove 113 formed between ribs 112, 112, with the result that IC 110 cannot be correctly positioned. This makes it difficult to sandwich the lead 111 between the side contact portion 108 and the movable side contact portion 106.
In order to avoid the above-mentioned disadvantages, as shown in FIG. 18(a), a positioning projection 114, which is formed on the socket main body 102, is brought into contact with the side surface of resin mold 115 so as to position IC 110. However, as shown in FIG. 18(b), if IC 110 is inserted in an inverted position, the side surface of resin mold 115 to be positioned is not present in the socket main body 102, so that the positioning of IC 110 cannot be carried out.
In connection with the IC socket of a clamshell type, there is proposed the technique in which a tip 121 of a contact pin 120 is engaged with a bend portion 122 of the lead 111 of IC 110 so as to position IC 110 as shown in FIG. 19 (for example, Unexamined Japanese Patent Publication Sho No. 63-25476, Unexamined Japanese Utility Model Publication Sho No. 63-25477). However, in such inventions, as shown in FIG. 20, the tip 121 of the contact pin 120 is not positioned to the socket main body 102. If the IC 110 is depressed by a cover 123, the contact pin 120 is bent and deformed, so that the position where the contact pin 120 and the lead 111 are contacted is shifted. As a result, there is a case in which the correct positioning of IC 110 cannot be expected.
Moreover, in connection with the IC socket of clamshell type, there is proposed the technique in which the lower surface of lead 111 and a side surface of resin mold 115 are supported by a pogo pin 130, which slides in up and down directions in the figure, allowing IC 110 to be positioned at a predetermined position of the socket main body 102 (Unexamined Japanese Patent Publication Hei No. 4-178574). However, according to such conventional structure, a movable portion 131 of the pogo pin 130 is mated with an engaging hole 133 of a fixing portion 132 of a movable portion 131 of the pogo pin 130. Further, the movable portion 131 of pogo pin 130 is elastically supported by a spring 134 attached in the engaging hole 133. For this reason, there is a limitation in a reduction in size of the pogo pin 130. Such structure cannot be applied to such IC 110 in which the pitch between leads 111 is narrow and the width of lead 111 is small as the present invention aims. Also, in such prior art, there is a problem in which the structure of pogo pin 130 is complicated and IC socket 100 becomes expensive. Further, in such prior art, there is a possibility that the movable portion 131 will rattle and fall down since a mate space is formed between the movable portion 131 of pogo pin 130 and the fixing portion 132. For this reason, high accurate positioning of IC 110 cannot be expected.
It is an object of the present invention to provide an IC socket, which can accurately position and support an IC with relatively a simple structure, and contact pins for use in the IC socket.
The invention of the first aspect is an IC socket comprising a socket main body for elastically supporting a cover having an IC insertion window formed thereon to be movable up and down; and a plurality of contact pins, which are attached to the socket main body, for connecting gull-wing shaped leads taken out of a side surface of an IC resin mold to an external electrical test circuit. Each of the contact pins comprises a base portion fixed to said socket main body; a first contact portion, which is extended from the base portion, for supporting the lead in a state that it is positioned by a pin support portion formed on the socket main body; and a second contact portion, which is connected to the base portion through a spring portion, for bending and deforming the spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the spring portion when the cover returns to an original position, whereby performing an electrical connection. A positioning step portion, which is engaged with the lead to position the IC, is formed on the first contact portion.
According to the invention of the first aspect, since the first contact portion of each contact pin, which supports the lead, is positioned by the pin support portion of the socket main body, the positioning step portion formed on the first contact portion is correctly positioned to the socket main body. Therefore, in the invention of the first aspect, when IC is inserted from the IC insertion window after the cover is depressed and the second contact portion is retracted from the first contact portion, the IC lead is engaged with the first positioning step portion of the first contact portion and IC is correctly positioned at a predetermined position of the IC socket. Thereafter, when the cover is returned to the original IC lead is surely sandwiched between the first contact portion of the contact pin and the second contact portion and the electrical test of IC can be correctly performed.
The invention of the second aspect is an IC socket comprising: a socket main body for elastically supporting a cover having an IC insertion window formed thereon to be movable up and down; and a plurality of contact pins, which are attached to the socket main body, for connecting gull-wing shaped leads taken out of a side surface of an IC resin mold to an external electrical test circuit. Each of the contact pins comprises a base portion fixed to the socket main body; a first contact portion, which is connected to the base portion through a first spring portion, for supporting the lead; and a second contact portion, which is connected to the base portion through a second spring portion, for bending and deforming the second spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the second spring portion when the cover returns to an original position, whereby performing an electrical connection. A pin support portion, which comes in contact with the first contact portion urged by a spring force of the first spring portion to position the first contact portion, is formed on the socket main body, and a positioning step portion, which is engaged with the lead to position the IC, is formed on the first contact portion.
According to the invention of the second aspect, since the first contact portion of each contact pin, which supports the lead, is pressed to the pin support portion of the socket main body by an elastic force of the first spring portion and the first contact portion is positioned by the pin support portion of the socket main body, the positioning step portion formed on the first contact portion is correctly positioned to the socket main body. Therefore, in the invention of the second aspect, when IC is inserted from the IC insertion window after the cover is depressed and the second contact portion is retracted from the first contact portion, the lead of IC is engaged with the first positioning step portion of the first contact portion and IC is correctly positioned at a predetermined position of the IC socket. Thereafter, when the cover is returned to the original position, the IC lead is surely sandwiched between the first contact portion of the contact pin and the second contact portion and the electrical test of IC can be correctly performed.
The invention of the third aspect is an IC socket comprising: a socket main body for elastically supporting a cover having an IC insertion window formed thereon to be movable up and down; and a plurality of contact pins, which are attached to the socket main body, for connecting gull-wing shaped leads taken out of a side surface of a resin mold of IC to an external electrical test circuit. Each contact pin comprises a base portion fixed to the socket main body; a first contact portion, which is extended from the base portion, for supporting the lead in a state that it is positioned by a pin support portion formed on the socket main body; and a second contact portion, which is connected to the base portion through a spring portion, for bending and deforming the spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the spring portion when the cover returns to an original position, whereby performing an electrical connection. A positioning step portion, which is engaged with the lead and the side surface of the resin mold to position the IC, is formed on the first contact portion.
According to the invention of the third aspect, since the first contact portion of each contact pin, which supports the lead, is positioned by the pin support portion of the socket main body, the positioning step portion formed on the first contact portion is correctly positioned to the socket main body. Therefore, in the invention of the third aspect, when IC is inserted from the IC insertion window after the cover is depressed and the second contact portion is retracted from the first contact portion, the IC lead and the side surface of the resin mold are engaged with the first positioning step portion of the first contact portion and IC is correctly positioned at a predetermined position of the IC socket. Thereafter, when the cover is returned to the original position, the IC lead is surely sandwiched between the first contact portion of the contact pin and the second contact portion and the electrical test of IC can be correctly performed.
The invention of the fourth aspect is an IC socket comprising: a socket main body for elastically supporting a cover having an IC insertion window formed thereon to be movable up and down; and a plurality of contact pins, which are attached to the socket main body, for connecting gal-wing shaped leads taken out of a side surface of an IC resin mold to an external electrical test circuit. Each contact pin comprises a base portion fixed to the socket main body; a first contact portion, which is connected to the base portion through a first spring portion, for supporting the lead; and a second contact portion, which is connected to the base portion through a second spring portion, for bending and deforming the second spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the second spring portion when the cover returns to an original position, whereby performing an electrical connection. A pin support portion, which comes in contact with the first contact portion urged by a spring force of the first spring portion to position the first contact portion, is formed on the socket main body, and a positioning step portion, which is engaged with the lead and the side surface of the resin mold to position the IC, is formed on the first contact portion.
According to the invention of the fourth aspect, since the first contact portion of each contact pin, which supports the lead, is pressed to the pin support portion of the socket main body by an elastic force of the first spring portion and the first contact portion is positioned by the pin support portion of the socket main body, the positioning step portion formed on the first contact portion is correctly positioned to the socket main body. Therefore, in the invention of the fourth aspect, when IC is inserted from the IC insertion window after the cover is depressed and the second contact portion is retracted from the first contact portion, the IC lead and the side surface of the resin mold are engaged with the first positioning step portion of the first contact portion and IC is correctly positioned at a predetermined position of the IC socket. Thereafter, when the cover is returned to the original position, the IC lead is surely sandwiched between the first contact portion of the contact pin and the second contact portion and the electrical test of IC can be correctly performed.
The invention of the fifth aspect is that, in the invention of the first aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion. Then, the positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the outer side surface of the second lead portion.
According to the invention of the fifth aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third IC lead portion, and the second positioning surface of the positioning step portion is engaged with the outer surface of the second lead portion of IC. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the sixth aspect is that, in the invention of the second aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion. The positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the outer side surface of the second lead portion.
According to the invention of the sixth aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third IC lead portion, and the second positioning surface of the positioning step portion is engaged with the outer surface of the second IC lead portion. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the seventh aspect is that in the invention of the first aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion. The positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the inner side surface of the second lead portion.
According to the invention of the seventh aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third IC lead portion, and the second positioning surface of the positioning step portion is engaged with the inner surface of the second IC lead portion. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of eighth aspect is that in the invention of the second aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion. The positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the inner side surface of the second lead portion.
According to the invention of the eighth aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third IC lead portion, and the second positioning surface of the positioning step portion is engaged with the inner surface of the second lead portion of IC. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the ninth aspect is that in the invention of the first aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion. The positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the tip surface of third lead portion.
According to the invention of the ninth aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third IC lead portion, and the second positioning surface of the positioning step portion is engaged with the tip surface of the third IC lead portion. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the tenth aspect is that in the invention of claim 2 or 2, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion. The positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the tip surface of third lead portion.
According to the invention of the tenth aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third IC lead portion, and the second positioning surface of the positioning step portion is engaged with the tip surface of the third IC lead portion. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the eleventh aspect is that in the invention of the third aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion, and the positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the side surface of the resin mold.
According to the invention of the eleventh aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third lead portion of IC, and the second positioning surface of the positioning step portion is engaged with the side surface of the IC resin mold. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the twelfth aspect is that in the invention of the fourth aspect, the lead has a first lead portion, which projects substantially horizontally from the side surface of the resin mold, a second lead portion, which is bent from the first lead portion, and a third lead portion, which is bent substantially horizontally from the second lead portion, and the positioning step portion has a first positioning surface, which supports the third lead portion, and a second positioning surface, which is engaged with the side surface of the resin mold.
According to the invention of the twelfth aspect, when the IC lead is engaged with the positioning step portion of the first contact portion positioned with respect to the socket main body, the first positioning surface of the positioning step portion supports the third lead IC portion, and the second positioning surface of the positioning step portion is engaged with the side surface of the IC resin mold. As a result, IC is correctly positioned and supported at the predetermined position of the IC socket.
The invention of the thirteenth aspect is IC socket contact pins, which are attached to a socket main body, which elastically supports a cover having an IC insertion window formed thereon to be movable up and down, for connecting gal-wing shaped leads taken out of a side surface of a IC resin mold to an external electrical test circuit. Each contact pin comprises a base portion fixed to the socket main body; a first contact portion, which is extended from the base portion, for supporting the lead in a state that it is positioned by a pin support portion formed on the socket main body; and a second contact portion, which is connected to the base portion through a spring portion, for bending and deforming the spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the spring portion when the cover returns to an original position, whereby performing an electrical connection. A positioning step portion, which is engaged with the lead to position the IC, is formed on the first contact portion.
The invention of the fourteenth aspect is IC socket contact pins, which are attached to a socket main body, which elastically supports a cover having an IC insertion window formed thereon to be movable up and down, for connecting gull-wing shaped leads taken out of a side surface of a IC resin mold to an external electrical test circuit. Each contact pin comprises a base portion fixed to the socket main body; a first contact portion, which is connected to the base portion through a first spring portion and which is pressed to a pin support portion formed on the socket main body by a spring force of the first spring portion so as to be positioned, for supporting the lead; and a second contact portion, which is connected to the base portion through a second spring portion, for bending and deforming the second spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the second spring portion when the cover returns to an original position, whereby performing an electrical connection. A positioning step portion, which is engaged with the lead to position the IC, is formed on the first contact portion.
The invention of the fifteenth aspect is IC socket contact pins, which are attached to a socket main body, which elastically supports a cover having an IC insertion window formed thereon to be movable up and down, for connecting gal-wing shaped leads taken out of a side surface of an IC resin mold to an external electrical test circuit. Each contact pin comprises a base portion fixed to the socket main body; a first contact portion, which is extended from the base portion, for supporting the lead in a state that it is positioned by a pin support portion formed on the socket main body; and a second contact portion, which is connected to the base portion through a spring portion, for bending and deforming the spring portion by being pressed by the cover when the cover is depressed, and for guiding the IC lead onto the first contact portion after retracting from the first contact portion, and for sandwiching the lead between the first contact portion and the second contact portion by an elastic restoring force of the spring portion when the cover returns to an original position, whereby performing an electrical connection. A positioning step portion, which is engaged with the lead and the side surface of the resin mold to position the IC, is formed on the first contact portion.
The invention of the sixteenth aspect is IC socket contact pins, which are attached to a socket main body, which elastically supports a cover having an IC insertion window formed thereon to be movable up and down, for connecting gal-wing shaped leads taken out of a side surface of an IC resin mold to an external electrical test circuit. Each contact pin comprises a base portion fixed to said socket main body; a first contact portion, which is connected to said base portion through a first spring portion and which is pressed to a pin support portion formed on said socket main body by a spring force of said first spring portion so as to be positioned, for supporting said lead; and a second contact portion, which is connected to said base portion through a second spring portion, for bending and deforming said second spring portion by being pressed by said cover when said cover is depressed, and for guiding said IC lead onto said first contact portion after retracting from said first contact portion, and for sandwiching said lead between said first contact portion and said second contact portion by an elastic restoring force of said second spring portion when said cover returns to an original position, whereby performing an electrical connection. A positioning step portion, which is engaged with said lead and the side surface of said resin mold to position said IC, is formed on said first contact portion.